The advent of virtualization technologies for computing resources has provided benefits with respect to managing large-scale computing resources for many customers with diverse needs. In addition, virtualization technologies have allowed various computing resources or computing services to be efficiently and securely shared by multiple customers. For example, virtualization technologies may allow a single physical host (e.g., a single physical computing machine) in a service provider environment to be shared among multiple customers by providing each customer with one or more computing instances hosted by the single physical host using a hypervisor. A computing instance may be a guest machine acting as a distinct logical computing system that provides a customer with the perception that the customer is the sole operator and administrator of a given virtualized hardware computing resource.
A messaging service operating in the service provider environment may provide reliable asynchronous message delivery to the computing instances. The messaging service may function as a broker that provides a software and/or hardware infrastructure to support sending and receiving of messages between computing instances and other components in the service provider environment. The messaging service may provide a reliable, fail-safe and scalable hosted message queue, and the implementation of the message queue may result in various advantages. For example, the message queue may be redundantly stored across multiple geographic regions in the service provider environment to increase robustness. In addition, the message queue may provide message storage when computing instances are busy or unavailable.